1. Field of the Invention
The present invention relates to a PDP(Plasma Display Panel), and in particular to a structure for a discharge sustaining electrode which makes it possible to generating a surface discharge in a certain discharge space when a discharge voltage is supplied to a display apparatus which uses a plasma.
2. Description of the Background Art
Generally, a PDP(Plasma Display Panel) is a plane display apparatus which is capable of displaying a motion picture or a still picture using a gas charge phenomenon and is classified into a 2-electrode type, a 3-electrode type and a 4-electrode type. The 2-electrode type is directed to applying a voltage for an addressing and sustaining operation using 2 electrodes, and the 3-electrode type is directed to a surface discharge type and is switched or sustained based on a voltage applied to an electrode installed at a lateral surface of a discharge cell.
FIGS. 1 through 4 illustrate a conventional 3-electrode surface discharge type PDP as a representative example.
FIG. 1 is a perspective view illustrating a panel, FIG. 2 is a cross-sectional view illustrating pixels, FIG. 3 is a view illustrating an electrode, and FIG. 4 is a view illustrating a state for checking a short circuit of a discharge sustaining electrode. FIG. 2 illustrates a state that an upper substrate is rotated at an angle of 90xc2x0.
The 3-electrode surface discharge type PDP includes a front substrate 1 which is a display surface of an image formed of an effective portion 1a and a non-effective portion 1b, and a back substrate 2 installed parallely to the front substrate 1 at a certain distance therebetween.
In the front surface 1, a plurality of a pair of discharge sustaining electrodes 6 are parallely crossing the effective portion 1a at each pixel for sustaining a light emitting phenomenon of the cells based on a discharging operation. Each sustaining electrode is formed of a transparent electrode 6a made of a glass material for preventing a decrease of an aperture ratio, and a metallic electrode 6b which is formed along one side of the transparent electrode 6a and decreases the resistance. In addition, there are further provided a dielectric layer 7 for limiting a discharging current of two electrodes and insulating the electrodes, and a protection layer 8 formed on the dielectric layer 7.
The back substrate 2 includes a partitioning wall 3 for forming a plurality of discharge spaces, namely, separating the cells, a plurality of address electrodes 4 for performing an address discharge and generating a vacuum violet ray at a portion where the address electrodes 4 cross with the discharge sustaining electrodes 6 on the front substrate 1, and a luminescent material 5 which emits a visual ray for displaying an image during the address discharge.
The light emitting operation of a certain pixel in the conventional PDP will be explained with reference to the accompanying drawing.
First, when a discharge start voltage is supplied between two discharge sustaining electrodes 6 which are provided in pair form at a certain cell, a surface discharge is generated between two electrodes, so that wall electric potentials are formed on the inner surface of a certain discharge space.
When an address discharge voltage is supplied to one of two discharge sustaining electrodes 6 and a corresponding address electrode 4, a writing discharge occurs in the interior of the cell. Thereafter, when a sustaining discharge voltage is supplied to two discharge sustaining electrodes 6 of a corresponding cell, a sustaining discharge occurs between the discharge sustaining electrodes 6 due to the electric potential particles generated during an address discharge with the address electrode 4, so that a light emitting operation of the cells is performed for a certain period.
Namely, an electric field is generated in the interior of the cells by a discharge between the electrodes, and a small amount of electrons of the discharge gas is accelerated, and the accelerated electrodes collide with a neutron particle. The particles are ionized into electrons and ions, so that the discharge gas is changed to a plasma state, and a vacuum violet ray is generated. The thusly generated violet ray excites the luminescent material 5 for thereby generating a visual ray, and the thusly generated visual ray is emitted to the outside through the effective portion 1a of the front substrate 1, so that a certain cell is light-emitted, and an image display is implemented.
When fabricating the PDP, in the sustaining electrode 6 formed of the transparent electrode 6a and the metallic electrode 6b, the metallic electrode 6b is easily damaged by a foreign substance generated during the fabrication process or an external impact, and a short circuit by which a certain conduction is made with another neighboring electrode may occur. In a state that the electrode is disconnected or short-circuited, if the PDP is fabricated, an erroneous discharge may occur between the electrodes.
In order to prevent the disconnection and short circuit problems, the disconnection and short-circuit checking operations are performed after forming an electrode pattern. As shown in FIG. 4, a power supplied pad portion 1c formed at the non-effective portion 1b of the metallic electrode 6b and another end portion of the, namely, a checking probe 10 are connected for thereby checking a disconnection and short circuit problem. As another method, both ends of the metallic electrode 6b are contacted with the probe 10 for thereby performing a checking operation.
However, in the conventional discharge sustaining electrode 6, in the case of the metallic electrode 6b made of a non-transparent material, in order to minimize the decrease of the transmittance of the visual light through the front substrate 1 during a discharge between the electrodes, a certain width xe2x80x9cdxe2x80x9d is maintained. When using a 60-pin short circuit checking unit, it is impossible to accurately contact the probe with the metallic electrode 6b during an automated process. In this case, if the contact state of the entire electrode lines and the checking probe is not checked, it is impossible to implement an accurate checking operation.
Accordingly, it is an object of the present invention to provide a PDP electrode which makes it possible to selectively increase the width of a metallic electrode in a range which does not affect the transmittance, so that it is possible to implement a quick and reliable disconnection and short-circuit checking operation for a metallic electrode which is generally designed to have a minimum line width for a transmittance of a visual ray, whereby it is possible to implement a stable disconnection and short-circuit checking operation for the electrodes.
To achieve the above objects, there is provided a PDP electrode having a metallic electrode provided with an end portion width in the non-effective portion of the screen greater than the electrode width in the effective portion, wherein a PDP(Plasma Display Panel) includes a substrate formed of a screen effective portion and non-effective portion, an electrode consists of transparent electrode and metallic electrode having a certain width in the effective portion, and each electrode has one end extended toward the non-effective pad portion.
One end of the metallic electrode having a greater width is positioned at another end of the pad portion.
The width of the metallic electrode in the screen non-effective portion is the same as or smaller than the width of the transparent electrode.
Additional advantages, objects and features of the invention will become more apparent from the description which follows.